kernel_optimize_test/include
Glauber Costa 3f13461939 memcg: decrement static keys at real destroy time
We call the destroy function when a cgroup starts to be removed, such as
by a rmdir event.

However, because of our reference counters, some objects are still
inflight.  Right now, we are decrementing the static_keys at destroy()
time, meaning that if we get rid of the last static_key reference, some
objects will still have charges, but the code to properly uncharge them
won't be run.

This becomes a problem specially if it is ever enabled again, because now
new charges will be added to the staled charges making keeping it pretty
much impossible.

We just need to be careful with the static branch activation: since there
is no particular preferred order of their activation, we need to make sure
that we only start using it after all call sites are active.  This is
achieved by having a per-memcg flag that is only updated after
static_key_slow_inc() returns.  At this time, we are sure all sites are
active.

This is made per-memcg, not global, for a reason: it also has the effect
of making socket accounting more consistent.  The first memcg to be
limited will trigger static_key() activation, therefore, accounting.  But
all the others will then be accounted no matter what.  After this patch,
only limited memcgs will have its sockets accounted.

[akpm@linux-foundation.org: move enum sock_flag_bits into sock.h,
                            document enum sock_flag_bits,
                            convert memcg_proto_active() and memcg_proto_activated() to test_bit(),
                            redo tcp_update_limit() comment to 80 cols]
Signed-off-by: Glauber Costa <glommer@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29 16:22:28 -07:00
..
acpi
asm-generic mm: pmd_read_atomic: fix 32bit PAE pmd walk vs pmd_populate SMP race condition 2012-05-29 16:22:24 -07:00
crypto
drm ttm: add prime sharing support to TTM (v2) 2012-05-23 10:46:27 +01:00
keys
linux mm/memcg: apply add/del_page to lruvec 2012-05-29 16:22:28 -07:00
math-emu
media [media] patch for Asus My Cinema PS3-100 (1043:48cd) 2012-05-20 16:05:02 -03:00
memory
misc
mtd UBI: amend commentaries WRT dtype 2012-05-20 20:25:59 +03:00
net memcg: decrement static keys at real destroy time 2012-05-29 16:22:28 -07:00
pcmcia
rdma Merge branches 'core', 'cxgb4', 'ipath', 'iser', 'lockdep', 'mlx4', 'nes', 'ocrdma', 'qib' and 'raw-qp' into for-linus 2012-05-21 09:00:47 -07:00
rxrpc
scsi isci update for 3.5 2012-05-21 12:17:30 +01:00
sound ASoC: Last minute updates 2012-05-22 02:58:55 +02:00
target
trace mm: vmscan: remove reclaim_mode_t 2012-05-29 16:22:19 -07:00
video arm-soc: First batch of cleanups 2012-05-22 09:23:24 -07:00
xen xen: do not map the same GSI twice in PVHVM guests. 2012-05-21 14:11:36 -04:00
Kbuild